Arsenic exposure increases maternal but not cord serum Ig G in B angladesh

Background Thousands of pregnant women are exposed to arsenic ( A s), which has been shown to lead to a higher risk of maternal and infant morbidity. We hypothesized that A s‐induced modifications to the humoral immune system may be partly responsible, and examined the relationship between A s and immunoglobulin G ( IgG ). Methods Pregnant women were recruited in A s‐contaminated rural areas in B angladesh. Blood and urine samples, and questionnaire data were collected. We analyzed data from 202 pregnant women and a subset of 121 mother–infant pairs. Urinary A s was measured on inductively coupled plasma–mass spectrometry and adjusted with specific gravity ( U ‐ As SG ). Maternal ( IgG mat ) and cord ( IgG cord ) serum total IgG were measured using immunoturbidity assay. Results The geometric mean U ‐ As SG ( n = 202) was 69 μg/L (range, 3.1–1356 μg/L). Urinary‐ As SG was significantly associated with I g G mat ( n = 202; (r = 0.24; 95% confidence interval [CI]: 0.10–0.36; P < 0.001) and remained so after the inclusion of maternal‐associated variables in a multiple‐regression model (β = 1.26; 95%CI: 0.47–2.05; P < 0.01). U ‐ As SG , however, was not significantly associated with IgG cord ( n = 121), while IgG mat and IgG cord were also not associated with each other. Conclusions Maternal A s exposure was positively associated with IgG mat but not IgG cord . Elevated IgG mat may have implications as regards maternal morbidity and the placental transfer of specific IgGs . Further studies are required to better understand how A s may affect maternal and child health by modifying the humoral immune system.